1. Field of the Invention
The present invention relates to the field of flow valves as used in the filling and discharge of fluid from a tank.
2. Description of the Related Art
There are several different kinds of float valves that are used to control the filling of tanks. A basic float valve system is the direct-operated float valve. This system is installed in the upper part of a tank and when the tank is full the float pushes or pulls a piston resulting in the stoppage of flow into the tank. When the pressure is high, the float doesn't have enough power to stop the flow of fluid which results in leaks. To overcome this issue in larger tanks, more sophisticated float valves are utilized which results in higher cost.
There are other valves, such as pilot operated, that may be used in high pressures or with large diameter pipes. In this system, when the tank is full, the valve is closed using line pressure. These types of valves are complex and require multiple parts to ensure proper function.
The methods listed above require a pipe to fill the tank and an additional pipe to discharge liquid from the tank. This requires additional cost to construct, maintain, and increases the risk of problems occurring within the lines.
There is a need for a double action float valve that can work on a single line for both inflow and outflow as well as in high pressure applications.